In the related art, there has been a vehicle seat device in which air bags (bladders) configured to be provided inside a seat are expanded and contracted, so that the support shape of the seat can be changed. For example, a seat device disclosed in JP 2010-233898 A (Reference 1) includes a plurality of air bags configured to be provided inside a seat, a flow path having a shared section and communicating with each of the air bags, and an air pump that pumps air to each of the air bags via the flow path. The seat device further includes a plurality of intake valves each of which is provided at a flow path position at an upstream of one of the air bags when air is pumped into each of the air bags, and an exhaust valve (an integrated exhaust valve) provided at a flow path position communicating with the shared section. In addition, each of the air bags is expanded and contracted by controlling operations of the air pump, each of the intake valves, and the exhaust valve.
That is, when each air bag is filled with air, the air pump is driven in a state where the intake valve provided at the upstream of the target air bag is opened, and the exhaust valve is closed. When air is discharged from the air bag, the intake valve corresponding to the target air bag is opened and the exhaust valve provided at the flow path position communicating with the shared section is opened in a state where the air pump is stopped. As described above, when the internal air of each air bag is discharged to the outside, one exhaust valve is used in common, thereby achieving the simplification of the structure.
However, in many cases, the sizes (internal capacities) of air bags provided inside a vehicle seat are set depending on seat positions where the air bags are arranged. Thus, in the above described configuration of the conventional technology, in which one exhaust valve is shared, there is a problem in that when a seat support shape is changed by discharging internal air filled in each of air bags, a difference is likely to occur in the operation speed. Then, there is a possibility that an occupant seated on the seat may feel uncomfortable, and in this respect, there is still room for improvement.
Thus, a need exists for a vehicle seat device and an intake and exhaust valve device which are not susceptible to the drawback mentioned above.